Path to power: Senate races to watch on election night

Washington DC: Republicans have a huge advantage as they seek to hold or expand their 51-49 Senate majority, with the battle for control running mostly through states that President Donald Trump won in 2016.

Out of the 35 Senate contests taking place Tuesday, 10 involve Democratic incumbents seeking re-election in states that Trump won, often handily. He's spending much of the final week before the election traveling to those states in the hope that it will nudge his supporters to the polls.

Meanwhile, Democratic hopes of taking the Senate hinge on nearly all of their incumbents winning a difficult task and on flipping seats in a few states that lean Republican, most notably Arizona, Tennessee and Texas.

Democratic Sen. Joe Donnelly is trying to fend off Republican businessman Mike Braun in a state that Trump won by 19 percentage points.

Donnelly is Indiana's lone Democrat elected statewide and has sought to align himself with Trump on the hot-button issue of expanding the border wall with Mexico. He has portrayed himself as a moderate who works with both parties to pass legislation. "I go against my party all the time," he said recently.

Braun has sought to question Donnelly's independence and describes him as a career politician. He notes that Donnelly supported Hillary Clinton's bid for the presidency and sided with the vast majority of Democratic senators in voting against the confirmation of Supreme Court Justice Brett Kavanaugh.

Democratic Sen. Joe Manchin is a former governor in search of a second full Senate term representing a state that supported Trump by a whopping 42 percentage points in 2016. His opponent is Patrick Morrisey, a two-term state attorney general and staunch Trump supporter.

Manchin has made maintaining health care protections for pre-existing conditions a major focus of his campaign and has hit Morrisey for joining a lawsuit challenging the constitutionality of the Affordable Care Act. He was the only Democrat to have voted for Kavanaugh. He also voted for Trump's first Supreme Court nominee, Neil Gorsuch.

Morrisey calls Manchin a liberal who only acts bipartisan around Election Day.

Democratic Sen. Bill Nelson is seeking a fourth term in the race against Republican Gov. Rick Scott. Scott has spent millions of dollars out of his own personal fortune to help fund his campaign. He has said that he would work to cut taxes and regulation if sent to Washington.

The two have clashed sharply on gun violence, a big issue in Florida following the February shootings at Marjory Stoneman Douglas High School.

Nelson has stressed that he favors a ban on military-style assault weapons and implementing a comprehensive system of background checks. Scott signed legislation in Florida that requires anyone wanting to buy a gun to be 21 years old, but the bill didn't include a ban on assault weapons.

The two have also differed on health care, with Nelson calling for strengthening the Affordable Care Act, but Scott calling the law deeply flawed and costly.

Democratic Sen. Claire McCaskill is running for a third term against state Attorney General Josh Hawley. Trump won Missouri by nearly 19 percentage points, and the state has shifted from a battleground to strongly Republican in recently elections.

McCaskill is touting herself as a moderate: "Claire's not one of those crazy Democrats. She works right in the middle and finds compromise," says one of her recent radio ads.

Hawley has tried to cast McCaskill as a "party-line liberal." The candidates have also tangled over Hawley joining a lawsuit filed by a group of Republican attorneys general to overturn the Affordable Care Act.

Trump has traveled several times to Missouri to campaign for Hawley, repeatedly describing the state's 38-year-old attorney general as a "star." Polls close at 8 p.m. EST

Democratic Sen. Robert Menendez is facing a tough re-election fight, and it has nothing to do with Trump. Rather, allegations of corruption have alienated some New Jersey voters. His bribery trial ended last year with a hung jury.

Prosecutors decided not to retry the case, but the Senate Ethics Committee followed up with a report that said his actions advancing the personal and business interests of a top donor "reflected discredit upon the Senate."

Democratic groups have spent millions in the state to boost Menendez in his race against Republican Bob Hugin, a former pharmaceutical executive who has tapped his own wallet for 24 million to finance a TV-ad-heavy campaign.

Democrats have more than 900,000 additional registered voters than Republicans in New Jersey, and Trump's low ratings in the Garden State could give Menendez a boost.

Republican Rep. Marsha Blackburn is running against former two-term Democratic Gov. Phil Bredesen in a state Trump won by 26 percentage points.

Blackburn would be the state's first female senator if elected. She has served eight terms in the House and is viewed as one of the more conservative members of that chamber.

Bredesen is trying to brandish his credentials as a centrist. He has said he will support or oppose Trump based on his specific ideas and how they affect Tennessee. The two are running to replace retiring Sen. Bob Corker, a Republican who has frequently clashed with Trump.