When it comes to political drama, nothing beats Texas.

Last year, the Lone Star State hosted a hard-fought Senate contest, as well as several intriguing congressional matchups. The results revealed that Texas is more competitive than it's been since the 1990s.

Now it's likely that Texas will be the most important battleground in the country for the 2020 elections.

Yes, Texas.

A Quinnipiac University Poll released last week showed that President Donald Trump faces trouble in Texas, running in a virtual tie with Beto O'Rourke, a former El Paso congressman, and two other top Democrats, former Vice President Joe Biden and Vermont Sen. Bernie Sanders.

The state has been trending to swing status for the last two election cycles. In 2014, Republican Greg Abbott beat former state Sen. Wendy Davis by 20 percentage points to become governor. Two years later, Trump beat Hillary Clinton by only 9 points. And last year, Republican incumbent Sen. Ted Cruz won re-election against O'Rourke by 2.6 percentage points.

Other 2018 down-ballot contests show the trend is real. Lt. Gov. Dan Patrick, Attorney General Ken Paxton and Agriculture Commissioner Sid Miller all won by 5 percentage points or less. They won by at least 20 percentage points in 2014.

Democrats gained 12 seats in the Texas House and two seats in the Senate. They also ousted Republican congressional incumbents Pete Sessions of Dallas and John Culberson of Houston.

Republicans are not mortally wounded. The GOP still has a structural advantage in statewide elections, as evident in their sweep of top-ticket races last year. If Republicans are energized, they'll be tough to overcome.

So 2020 is setting up as a high-stakes struggle between Democrats looking to make additional inroads and Republicans trying to re-establish dominance.

The result could change national and Texas politics for a generation.

Here are the three factors that make Texas a competitive state.

Race for the White House

Trump's hopes for re-election, analysts say, hinge on his ability to again win the Rust Belt states of Michigan, Wisconsin and Pennsylvania. Before 2016, Democrats relied on a Midwestern firewall to boost their chances in presidential elections. The last time a Republican won Wisconsin was 1984, when Ronald Reagan routed former Vice President Walter Mondale on the way to re-election.

Trump has been the major motivator for Democratic Party turnout, with the midterm elections a referendum on his leadership. With him on the ballot in 2020, turnout will be high from both Democrats and Republicans.

But if Trump doesn't win Texas, it's a wrap for Republicans. They must win the state's large bounty of delegates to have a shot at holding the presidency, given that Democrats control the delegate-rich states of California and New York.

So Trump and Republicans will have to fortify Texas, and there's a chance the incumbent president could watch the Lone Star State slip away. Even if he does win the state, Democrats will have made him invest time and resources here, which Republicans haven't had to do since Democrat Jimmy Carter beat incumbent Gerald Ford in 1976.

And two Texas Democrats will be in the presidential mix. Former San Antonio mayor and Obama administration Housing secretary Julián Castro has launched his campaign, while O'Rourke is expected to announce his bid soon.

Race for Senate

O'Rourke has been deliberating on how to best serve the country: challenge incumbent Sen. John Cornyn, or run for president. Last week I reported that O'Rourke is not running for Senate, which paves the way for a presidential bid.

Many Texas Democrats hoped O'Rourke would run against Cornyn because it would have given them their best chance to win their first statewide contest since 1994.

But there are also national implications. Last year O'Rourke's campaign, with his $80 million in donations and formidable field operation, helped down-ballot candidates win congressional and Texas legislative races.

Senate Minority Leader Chuck Schumer of New York had tried to convince O'Rourke to face Cornyn, knowing he could have a similar Pied Piper effect in 2020.

Looks like Schumer couldn’t close the deal: Sources: Beto O'Rourke won't challenge John Cornyn for Senate, paving way for presidential bid | Elections 2020 | Dallas News https://t.co/Qvs6jtQZyg — Senator John Cornyn (@JohnCornyn) February 28, 2019

Even without O'Rourke running for Senate, Democrats are confident their base voters will turn out at a higher rate than 2018. And they're hoping Trump will scare independent voters enough that they vote for Democrats up and down the ballot.

Cornyn, who had the benefit of watching how the Cruz-O'Rourke race played out, said he will be prepared for a serious challenge.

Democrats who could challenge him include Rep. Joaquin Castro of San Antonio, Air Force veteran and former congressional candidate MJ Hegar, retired Air Force colonel and 2018 agriculture commissioner candidate Kim Olson, and Davis, the former state senator.

Down-ballot action

National Democrats are targeting six Republican congressional incumbents in Texas, including Coppell Rep. Kenny Marchant. Other Texas Republican targets are Reps. John Carter of Round Rock, Michael McCaul of Austin, Pete Olson of Sugar Land, Chip Roy of Austin and Will Hurd of San Antonio.

Texas Democrats will also look to gain ground in the state Legislature. Dallas County has only two remaining Republican incumbents — Reps. Morgan Meyer of University Park and Angie Chen Button of Garland. Joanna Cattanach has already said she'll try to avenge her close loss last year to Meyer.

Collin County is also trending toward the middle, as evident by several close legislative races there, and you can expect Democrats to run a slate of candidates for the Supreme Court and the Court of Criminal Appeals.

Though the presidential and Senate race will propel most of the voter turnout next year, down-ballot contests often ignite Democratic and Republican base voters. That adds critical votes to the statewide numbers and another layer of drama to the process.

If you like competitive politics, stay tuned to what's happening in Texas.