Washington (CNN) President Donald Trump's stunning victory was regarded by many Republicans as the possible beginning of a new era of GOP dominance. It's been the exact opposite.

When Trump was inaugurated, there were 241 Republicans in the House. With the retirement of Florida Rep. Ted Yoho on Tuesday, 104 of them have either retired, been defeated or are not running again in 2020, according to stats provided by Cook Political Report House editor David Wasserman

That's a remarkable number. Almost half (43%) of the Republicans who were in the House when Trump became the 45th President are either already gone or in the process of going.

Now, not all of that attrition can be directly attributed to Trump. There is always some level of turnover in Congress as people run for other offices, retire or get enmeshed in scandal and leave. That goes double when your party goes from the House majority to the House minority, which is what happened for Republicans in the 2018 midterms. Being in the House majority is great. Being in the House minority is brutal; you have almost no control of your schedule and no ability to move meaningful legislation of any sort.

But Trump bears at least some responsibility for his party's losses in the 2018 election, as Democratic candidates across the country -- and especially in the suburbs -- ran against him and his version of conservatism as much as they did against their actual opponents.

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