Nov. 6 (UPI) -- Americans have one last chance to go to the polls on Election Day Tuesday, casting ballots according to their contentment or disgust with how things are going from the White House on down.
Many see Tuesday's congressional and state races as a referendum on President Donald Trump and his agenda.
The election has already set records for turnout with more than 30 million votes cast during early voting.
Michael McDonald, an associate professor at the University of Florida who researches American elections, said on Twitter 28 states and the District of Columbia have surpassed their 2014 early voting totals.
In two of those states, Nevada and Texas, early voting surpassed all ballots cast in the midterms four years ago.
There's a lot riding on the congressional and gubernatorial races -- leaders who will have the power to reshape district maps after the 2020 Census. Here are some of the highlights of what's at stake o Tuesday.
The Trump referendum
Trump has been active on the campaign trail trying to rally his base to the polls. He has taken a personal interest in the U.S. Senate race in Montana, where he's traveled four times since July.
Democratic incumbent Jon Tester is in a tight race to keep his seat against Republican challenger Matt Rosendale. With Trump's help, Rosendale has closed the gap on Tester, who had led the race by 9 points in a poll last month (47-38).
Trump has also campaigned in recent days in West Virginia and Indiana, where vulnerable Senate Democrats Joe Manchin and Joe Donnelly are holding on to slim leads.
Trump vowed to unseat Tester after he led a Democratic effort to block former White House doctor Adm. Ronny Jackson from being appointed to lead the Department of Veterans Affairs.
In most of his rallies, Trump has played up immigration issues, like the caravan of Central American migrants in Mexico headed for the United States -- and the tax cuts from Republicans this year.
In political ads around the country, perhaps no one has been mentioned more than Trump. According to a survey of television and Facebook ads by the Wesleyan Media Project, the president has been mentioned in about 13 percent of all television ads and 17 percent of Facebook ads.
Republicans have targeted Senate minority leader Chuck Schumer in ads. His name has been invoked in 11.3 percent of Republican television ads this season. House minority leader Nancy Pelosi has been mentioned in 7.1 percent of GOP ads.
"The economy is so good right now: highest wage increases in a decade, 250,000 new jobs, manufacturing jobs, hospitality, construction," Republican National Committee chairwoman Ronna McDaniel said in a statement last week.
"We are on a comeback and all Democrats want to do is stop that. ... It's a no-brainer, and we need to close strong and tell voters it is the economy, economy, economy."
Democrats, meanwhile, have mentioned Trump in 10 percent of their ads -- and have made taxes the top issue in their political advertising.
Tom Perez, chairman of the Democratic National Committee, countered McDaniel's positive economic news, arguing that voters feel squeezed by rising prices and are not feeling the economic progress.
"If you get $1 more on your paycheck and the cost of gasoline, the cost of healthcare, the cost of housing goes up by $3, you're not better off," Perez said Sunday. "We created more jobs in the last 21 months of the Obama administration than the first 21 months of the Trump administration. People need to feel that if they work a full-time job, they actually able to feed their families and not tread water."
History might be made in two states. In Florida, voters are deciding if Andrew Gillum will become the first African-American governor -- and in Georgia, Stacey Abrams could be the first black female governor anywhere in the country.
While Gillum, the Democratic mayor of Tallahassee, has held a slim lead in the last five state polls, he has consistently led GOP opponent Ron DeSantis.
Trump has hit Florida hard with two campaign trips this past week in an effort rally his base for DeSantis and current Florida Gov. Rick Scott, who is trying to unseat incumbent Democrat U.S. Sen. Bill Nelson.
In the same StPetePolls.org survey, Scott leads Nelson 49.1 percent to 47.5.
The Georgia race has been marred by voter suppression charges against Kemp and how he is applying the state's "exact match" voter identification law. A federal judge said Friday the state must change its procedures to make it easier for some people affected by the policy to vote, pointing out how the policy affected minorities disproportionately.
In Vermont, known for its independent streak, Democrat Christine Hallquist is fighting Republican incumbent Phil Scott to become the first openly transgender woman elected as governor. Experts have Scott leading by double-digits.
House in reach of Democrats
The House of Representatives is in play for the first time since President Barack Obama's first term. According to the latest polling, the Democrats have a shot of winning the 23 seats needed to seize the majority in the lower chamber.
Analysis website FiveThirtyEight gives Democrats a 7-in-8 chance to taking back the House.
"The House playing field is exceptionally broad this year, because of Republican retirements, an influx of Democratic cash and other factors," Nate Silver, the creator, and editor of FiveThirtyEight, said in a statement Saturday.
One of the "must-have" House races for both parties is in Florida's 26th District, where Republican incumbent U.S. Rep. Carlos Curbelo is fighting off a strong challenge from Democrat Debbie Mucarsel-Powell. Recent polling has them neck-and-neck.
Curbelo had tried to separate himself from Trump's tough immigration rhetoric in recent days, saying in a television interview he believed sending 15,000 U.S. troops to the country's southern border was an "overreaction."
Mucarsel-Powell, in the meantime, charged that Curbelo was trying to burnish his moderate credentials while voting with the Trump administration and Republicans 85 percent of the time.
Republicans feel better about Senate
While the House could flip, many Republicans feel more secure about keeping the Senate when the votes are officially counted Tuesday night.
FiveThirtyEight gives Republicans a 5-in-6 chance of holding the Senate majority, based on changes in several key races.
A KNXV-TV-OH Predictive Insights poll last week showed Arizona Republican Martha McSally with a seven-point lead over Democrat Kyrsten Sinema, who held a slim lead in previous polls for the seat to replace U.S. Sen. Jeff Flake.
"If Kavanaugh didn't happen, I think it'd be an extremely tight race," Noble told KNXV-TV. "If not, I'd actually say the edge would go to Sinema but after seeing the polling - seeing the results -- everything else -- I think that McSally will end up winning coming election night."
While there's been plenty of buzz around Sen. Ted Cruz and challenger Rep. Beto O'Rouke, experts say Cruz is likely to hold onto that seat -- as he leads by an average of 6 to 10 percent.
"Sen. Cruz is ahead due to his winning the 'gender gap.' He wins men 56-39 percent, while Representative O'Rourke can manage only a 52-45 percent edge among women."
Republicans may also be in position to pick off some Democratic seats. In South Dakota, incumbent Sen. Heidi Heitkamp trails GOP challenger Kevin Cramer by double-digits in some polling. In Missouri, Sen. Claire McCaskill was tied with challenger Josh Hawley in recent polling.
Big day for marijuana
The growing U.S. marijuana industry is hoping to expand even more Tuesday, with voters in four states weighing in on various legalization measures.
North Dakota will vote on allowing residents to grow, use and possess as much pot as they want, without government oversight. Michigan will vote on legalizing, taxing and regulating recreational-use pot, along with three other laws to allow medical use.
Missouri will vote on three plans to allow residents to grow, manufacture, sell and use marijuana with varying degrees of taxation and other provisions. Utah will vote whether to approve a medical cannabis measure.
Some 30 states have already legalized marijuana and the District of Columbia has legalized medical-use cannabis.
Alabama will decide a constitutional amendment defining "personhood" at conception, in a key abortion rights measure.
Oregon and West Virginia will vote on amending their constitutions to limit Medicaid abortion funding only to cases where the life of the mother is in danger, rape and incest.
Colorado, Michigan and Utah will decide on creating independent commissions for redistricting. Those states currently have legislators draw their own lines, like most states.
Florida will vote on expanding voting rights to felons, which could give an estimated 1.5 million their right to vote back.
Michigan and Nevada will decide on making voter registration automatic, and Maryland will decide on approving same-day registration and voting.