An overwhelming majority of Democrats think the House should impeach Trump. So do 15% of Republicans.

• On Tuesday, House Democrats announced the launch of a formal impeachment inquiry into President Donald Trump.
• An Insider poll conducted starting on Wednesday found Democrats are strongly in favor of impeachment, with 73% responding that the House should impeach Trump.
• Fifteen percent of Republicans polled also approve of impeachment.
• The numbers of respondents who back an impeachment inquiry into Trump - a precursor to impeachment - are even higher, regardless of political affiliation.
• Despite the support for impeachment, more than a quarter of Democrats said they think an impeachment inquiry will negatively impact their party electorally.
• Visit Business Insider's homepage for more stories.

The vast majority of Democrats polled by Insider on Wednesday and Thursday said they think the House of Represents should impeach President Donald Trump - and so did more than one in ten Republicans.

House Speaker Nancy Pelosi announced the launch of a formal impeachment inquiry into Trump on Tuesday, tied to a whistleblower complaint alleging that Trump had pressured Ukrainian President to investigate the son of former Vice President Joe Biden, a potential opponent in the 2020 presidential election.

The inquiry, which involves gathering evidence to build a case against Trump, is a precursor to official articles of impeachment being levied against the president.

More Democrats support impeachment than Republicans oppose it

On Wednesday and Thursday, Insider polled 1,096 American adults, asking "Impeachment is the first step in the process of removing a president from office. Do you think the House of Representatives should impeach President Trump?"

Results showed that 73% of those who plan to vote in their state's Democratic primary or caucus either "support" or "strongly support" impeachment. That's considerably higher than the Republican respondents who said they oppose the process: About 63% of Republican voters said they "oppose" or "strongly oppose" impeachment.

The full results:

• 50% of Democrats and 7% of Republicans "strongly support" impeachment.
• 23% of Democrats and 8% of Republicans "support" impeachment.
• 5% of Democrats and 15% of Republicans "oppose" impeachment.
• 4% of Democrats and 48% of Republicans "strongly oppose" impeachment.
• 17% of Democrats and 20% of Republicans "neither oppose nor support" impeachment, or they don't know

Fifteen percent of Republican voters actually support impeachment to some degree, the poll found.

An even higher proportion of respondents in both parties said they believe that launching an impeachment inquiry is the right thing to do.

The poll asked: "Do you believe launching a formal impeachment inquiry into President Trump for soliciting foreign interference in a US election is the right thing to do?"

• 55% of Democrats and 9% of Republicans said "definitely yes."
• 22% of Democrats and 13% of Republicans said "probably yes."
• 8% of Democrats and 25% of Republicans said "probably not."
• 6% of Democrats and 40% of Republicans said "definitely not."
• 8% of Democrats and 10% of Republicans said "I don't know."

Overall, 76% of self-identifying Democratic voters said they endorse an investigation, and so did 23% of Republicans.

Even though the vast majority Democrats back an impeachment inquiry, electoral backlash is a real concern

For Democrats, the support comes with a major caveat. When asked, "Do you believe launching a formal impeachment inquiry into President Trump will overall work out in Democrats' favor electorally?," a good chunk of the constituency said "probably would not" or "definitely would not."

In total, 28% of Democrats polled thought an impeachment inquiry will have negative consequences for their party electorally. An additional 25% were unsure of what kind of impact an impeachment inquiry would have in the next election cycle.

Read more:

POLL: Americans support the impeachment inquiry into Trump, but they worry about electoral blowback

A formal impeachment inquiry has been launched: Here's everything we know about the whistleblower complaint and Trump's phone call with Ukraine's president

Trump suggested the whistleblower who filed a complaint against him is guilty of treason, which is punishable by death

SurveyMonkey Audience polls from a national sample balanced by census data of age and gender. Respondents are incentivized to complete surveys through charitable contributions. Generally speaking, digital polling tends to skew toward people with access to the internet. SurveyMonkey Audience doesn't try to weight its sample based on race or income. Total 1,096 respondents collected September 25-26, 2019, a margin of error plus or minus 3.04 percentage points with a 95% confidence level. Download the respondent-level data here.