Two weeks into a House impeachment inquiry into President Donald Trump, only 30% of Americans say they're against impeaching the sitting president.

Insider's most recent poll found that 9.1% of Americans "oppose impeachment," while 20% "strongly oppose impeachment."

Conversely, a plurality of respondents, 47%, say they support impeaching Trump.

The numbers are consistent with Insider's last poll conducted in the wake of House Democrats' announcement of their investigation — but partisanship on the issue has grown.

Over 80% of Democrats polled said they support impeachment, while 75% of Republicans said they oppose it. Both figures are notable increases from our previous poll.

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Only 30% of Americans say they oppose impeaching President Donald Trump, according to Insider's most recent poll.

The number is unchanged from the first time Insider polled on the subject in the wake of House Speaker Nancy Pelosi's announcement of a formal impeachment inquiry into Trump, resulting from a whistleblower complaint alleging that Trump had encouraged the president of Ukraine to investigate former Vice President Joe Biden and his son, Hunter, for potential political gain leading up to the 2020 election.

Now, two weeks later, the consistent numbers suggest that Trump has been unable to rally opposition among voters to House Democrats' investigation.

Both polls surveyed a sample of more than 1,000 adults nationwide. Conducted September 26-27 and October 3-4 respectively, they each asked "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 from Insider's latest poll:

I strongly support impeachment , 30.9%

, 30.9% I support impeachment , 16.1%

, 16.1% I neither support nor oppose impeachment , 13.5%

, 13.5% I oppose impeachment , 9.1%

, 9.1% I strongly oppose impeachment , 20.0%

, 20.0% I don't know, 10.3%

Approximately 20% of respondents from both polls said they "strongly oppose impeachment," while 9 to 10% of respondents from both polls said they "oppose impeachment."

A plurality of respondents — 47% — said they support impeachment, an amount of support that stayed steady across the two polls. Of that 47%, most said they "strongly support impeachment."

Partisanship has grown on impeachment

In the time that has elapsed since the outset of the impeachment inquiry, partisanship has increased by a considerable measure, Insider found. Our previous poll found that 73% of respondents who plan to vote in their state's Democratic primary or caucus were in support of impeachment. So were 15% of self-identified Republican voters. Sixty-four percent of those who plan to vote in their state's Republican primary or caucus said they opposed impeachment.

Two weeks later, 82% of Democratic voters polled said they support impeaching Trump — a nine percentage point increase. Opposition from Republican voters, meanwhile, increased by 11 percentage points, to 75% — and Republican support for impeachment decreased to 10%. The shifts suggest that impeachment is becoming an increasingly polarizing topic between the left and the right.

But polling by both Insider and other organizations has found that a majority of Americans are in favor of impeachment inquiry — the discovery process leading up to articles of impeachment, or official charges of unlawful behavior, being levied against the president — and that number is growing regardless of partisanship.

Read more:

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Trump reportedly told allies that he's worried impeachment will ruin his resume

Swing voters are on the fence about impeaching Trump, but are more inclined to favor it

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 1,083 respondents collected October 4-5, 2019, a margin of error plus or minus 3.06 percentage points with a 95% confidence level.