President Donald Trump says he really hopes the Republican Party wins a special congressional election in Kansas.
The election will find a replacement for former Rep. Mike Pompeo, who now heads the CIA.
Kansas has long been a deep-red state, but the race between state Treasurer Ron Estes — a Republican — and Democrat James Thompson — a civil rights attorney — is tighter than many expected.
Libertarian Chris Rockhold is also running.
Trump sent out an automated call urging people in the fourth congressional district to vote for Estes, and the president tweeted about the race on Election Day.
"This is President Donald Trump. ... Ron is a conservative leader who's going to work with me to make America great again," Trump said in the call that The Wichita Eagle recorded.
Other Republicans are lending support as well.
Vice President Mike Pence recorded a similar call. House Speaker Paul Ryan sent out a fundraising email to Republican donors, and Sen. Ted Cruz was at a rally for Estes on Monday.
The head of the state's Republican Party told The Kansas City Star only about 20 percent of eligible voters are expected to turn out Tuesday.
Democratic candidate Thompson got a late surge of support, raising about $240,000 from thousands of donors in the last few days of the campaign.
This is the first special congressional election since Trump was elected president.
Pompeo is one of five members of the Trump Cabinet who will need special elections to find their replacements in Congress.