NASHVILLE, Tenn. (AP) - Democrat Andy Berke was overwhelmingly elected to a second term as Chattanooga mayor on Tuesday.

With all voting locations reporting, Berke had 64 percent, compared with 26 percent for the closest of three challengers.

Berke, a former state senator, was first elected mayor with more than 70 percent of the vote in 2013. This year Berke faced City Councilman Larry Grohn, former Council member David Crockett and architectural consultant Chris Long.

Berke's first term was marked by two tragedies: A school bus crash that left six children dead in December and the fatal shootings of four Marines and a sailor in 2015 by a man investigators say was inspired by foreign terrorists.

The race was decided Tuesday because Berke easily cleared more than 50 percent of the vote. If he hadn't he would have faced a runoff with his closest challenger on April 11.

About 20 percent of registered voters cast ballots in the election.

Berke far outraised his opponents, collecting $500,000 to their combined $62,000, the Chattanooga Times Free Press has reported. Berke had spent $358,000 as of the most recent campaign finance filings, and still had about $143,000 remaining on hand.

Berke's opponents said the incumbent has been preoccupied with potential bids for higher office. Grohn distributed what he described as internal documents showing Berke's plans for a higher statewide profile if Democrats had won last year's presidential election and he had secured a cabinet post.

Berke said the papers were in fact written as graduate school assignments by his chief of staff, Stacy Richardson.

The incumbent was also the subject of unwanted attention last year when the husband of top aide Lacie Stone alleged she was having an affair with the mayor - a claim Berke strongly denied.

Bobby Stone first made the allegation when he was arrested on domestic violence charges. Prosecutors later dropped the case after determining that Stone had not been read his Miranda rights to remain silent before he was interviewed by police and that Lacie Stone had made "inconsistent" statements about their altercation.

Challenger Crockett's platform included a call for separating Chattanooga from surrounding Hamilton County and save city residents from paying county taxes. Crockett wouldn't have had the authority to enact the proposal even if he had been elected. It would take an amendment to the state constitution to allow cities to declare themselves independent of counties.