If the Democratic Party candidate wins, President Donald Trump will have only himself to blame -- and perhaps, a savvier than expected opponent. A defeat would put the (former?) reality television star in elite company: Since 1952, only two incumbents have lost after winning a first term, while six have won, including Ronald Reagan and Barack Obama.

With strong economic numbers so far and no unpopular overseas wars, most incumbent U.S. leaders would have been assured victory. And scandals, which would have sunk others, haven't dented Trump's backing among his base and independent voters. (The impeachment investigation over the Ukraine issue may change that yet.)

Nonetheless, his chances are now a toss-up.

Yes, Trump consistently retains upwards of 90 percent support among Republicans. Fearful of crossing him because he could end their political careers, Republican lawmakers have rallied around him too.

Even something that could disrupt the global economy and allies like Japan, a Persian Gulf conflict, accidental or intentional, could help Trump. U.S. voters usually rally around their commander-in-chief in such instances, something that could put him over the top in a close race.

Still, issues are piling up.

The biggest one is the start of formal impeachment hearings by House Democrats on the new Ukraine scandal. They accuse him of trying to leverage military aid, which Trump had suspended, to force Kiev to investigate his potential Democratic opponent, former Vice President Joe Biden, and his son for corruption.

In a non-verbatim transcript released by the White House -- after the Democrats' move, Trump asked Ukraine President Volodymyr Zelensky in July to do the United States "a favor." Before that request, he said that Washington "has been very, very good to Ukraine. I wouldn't say that it's reciprocal necessarily." He added, after asking for the favor, "whatever you can do" with U.S. Attorney General William Barr "would be great" regarding the two Bidens. The whistleblower complaint, which set off the inquiries, echoes the Democrats' charge and adds that the White House tried to hide the verbatim transcript. Trump denies any wrongdoing.

With impeachment, the House acts as a prosecutor to indict and, if it decides to, the Senate holds a trial.

Regardless of the outcome of those investigations, views on Trump within the two parties are pretty set, and the Republican-controlled Senate is unlikely to convict to oust him. With hearings set and subpoenas being issued to potential witnesses in the scandal, more details and other related documents and conversations are likely to come out too. One key question is whether Trump loses support among moderate Republican and unaffiliated voters over this. In the past week, some polls are showing a shift toward supporting impeachment among independents. (Another is whether the proceedings drive more of his base supporters to turn out in 2020.)

Since taking office in 2017, Trump hasn't broken past 50 percent in his approval ratings -- a first for a modern president. And his disapproval has been consistently above 50 percent. Last November, his party lost its House majority because Trump alienated suburban voters, especially college-educated Republican women and independents.

The trade war with China and the direction of the economy could undermine the support of those that elected him too. One agricultural group executive at an August Congressional town hall in Nebraska said that farmers were "mad" about some of his policies, including the China trade battle. Indeed, 60 percent of registered voters surveyed thought a recession was coming in the next year and 43 percent were concerned that Trump's trade and economic policies would increase the chances of one, says a September Washington Post/ABC News poll.

With over a year left before the election, much can happen and inept Democrats could kick one into their own goal like in 2016. But what's clear today, like some recent presidential elections, is that it looks to be close.

(James Simms is a Forbes contributor, freelance reporter and television and radio commentator in Tokyo and is a former Wall Street Journal columnist and former Scripps Journalism Fellow at the University of Colorado.)