Democratic presidential candidate Kamala Harris is trimming staff and restructuring her struggling 2020 campaign to focus more on a make-or-break effort in the first nominating contest in Iowa, according to a campaign memo seen by Reuters.

Harris, who has slipped in opinion polls over the last three months, will be "all-in on Iowa" and redeploy field staff from New Hampshire, Nevada and California there, the memo said.

Why is Harris making changes?

The U.S. senator from California will also cut staff at the campaign's Baltimore headquarters, renegotiate contracts and reduce the salaries of her campaign manager and all consultants, according to the memo, which was first reported by Politico.

Harris has fallen into the middle of the crowded pack of candidates seeking the Democratic nomination to challenge Republican President Donald Trump in the November 2020 election, losing support since mid-summer and lagging behind top rivals in fundraising.

A RealClearPolitics average of national polls shows her dropping from 15 percent support in mid-July, good for second place behind Joe Biden, to about 5 percent now, putting her in fifth place among 18 Democratic candidates.

In the race for campaign cash, Harris has brought in about 36 million U.S. dollars since launching her bid earlier this year, according to the Center for Responsive Politics. That is well behind leaders and fellow senators Bernie Sanders, who has raised nearly 74 million U.S. dollars, and Elizabeth Warren, at 60 million U.S. dollars.

What's the new strategy?

Harris campaign manager Juan Rodriguez said in the memo the restructuring would bolster investments in Iowa, where Harris will spend the Thanksgiving holiday campaigning. Iowa hosts the first nominating contest on February 3.

"These decisions are difficult but will ensure the campaign is positioned to execute a robust Iowa ground game and a minimum 7-figure paid media campaign in the weeks leading up to the caucus," Rodriguez said.

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The campaign's presence in South Carolina, which hosts the fourth nominating contest and which Harris has made central to her strategy, will not be affected, the memo said.

A RealClearPolitics average of Iowa polls shows her tied for fifth place in Iowa with 2.7 percent support, well behind leaders Warren, Biden, Sanders and Pete Buttigieg, mayor of South Bend, Indiana, who are all in double digits.