Right now, 2018 is shaping up to be a good year for Democrats and a bad one for Republicans. In Congress, the GOP has failed to fulfill their signature campaign promise of repealing Obamacare. Donald Trump garners bad press every day and  then amplifies it through his twitter feed. The western world is looking to leaders besides the United States for the first time since World War II. And yesterday a poll came out saying the generic House ballot gives Democrats a 14-point advantage. Those are wave numbers.

So what could change the trajectory of an election that’s still 15 months away? Well, a lot of things could. The Democrats could screw up. The Republicans could get their act together. The economy could continue to improve for a majority of Americans. We could have another terrorist attack. And Donald Trump could stop tweeting. Just kidding.

Democrats, for their part, should continue to focus on the economy and less on Russia and Trump. If the wing of the party that believes 2018 should be a referendum on impeaching Trump wins out, we’ll probably see a backlash against overreach like Republicans hell bent on impeaching Bill Clinton saw 20 years ago. If Robert Mueller and his investigation find evidence of collusion or other wrong doing, then Democrats should let the process play out. Cheering for failure is not a good look.

They could also make protecting the rights of minorities the signature issue of the party in 2018, ignoring the needs of people of all stripes who have been left behind in the global economy. The party is having an argument on whether to focus on white working class voters, many of whom voted for Trump, or motivating minority voters, many of whom sat out the last election. It’s the wrong argument. The minority voters who sat out 2016 did so for the same reason that white voters who supported Obama in 2012 switched to Trump in 2016. They both don’t believe Washington is doing anything for them. It’s not an either-or situation. It’s both–and the economic argument crosses racial lines.

Republicans, for their part, could suddenly find unity and pass some serious legislation. After the failure of Obamacare repeal, they’ve turned to tax reform. That’s probably like moving from the hornet’s nest to the wasp’s nest. The last time we had a significant overhaul of the tax system was in 1986 and it was both contentious and bi-partisan. Taking on such a controversial problem is likely to divide people more than unite them, even if they successfully push it through (see the Affordable Care Act, 2010).

A terrorist attack could throw the election cycle into turmoil. Voters tend to favor Republicans more on national security issues and a large-scale attack could spur nationalism that drives people toward Trump and his anti-immigrant policies. Fear could significantly change the political landscape in the country.

Democrats need to focus on economic issues that provide broad, shared prosperity. Much of the middle class has seen its income stagnate since Reaganomics shifted the tax burden from the wealthy to the middle class and rewarded people who make money from investments more than people who make money from wages. Those policies affected people of all colors and nationalities and that’s who Democrats need in their coalition. The greatest threat to what should be a very successful election cycle for Democrats is a party that looks to divide the country by color, gender, sexuality, nationality, or disability instead of a party that offers a broad unifying message that unites people who just want a little economic security and hope for the future.