(Reuters) - A majority of Americans think President Donald Trump’s plan to send National Guard troops to the U.S.-Mexico border will be effective in combating illegal immigration in the short term, according to a Reuters/Ipsos poll from April 15-19.

Members of the Texas National Guard wait for Governor Greg Abbott to speak about security on the Mexico-U.S. border at Sergeant Tomas Garces Texas Army National Guard Armory in Weslaco, Texas, U.S., April 12, 2018. REUTERS/Loren Elliott

Here are some key findings from the poll:

THINKING LONG TERM

Fifty-five percent of U.S. adults think deploying the National Guard to the border will be effective in the short term, but only 49 percent think it will be effective in the long term. About 16 percent of Americans think it will be “very effective” short and long-term.

See graphic: tmsnrt.rs/2HDwaiT

PARTY LINES

Seventy-seven percent of Republicans think deploying the National Guard will be effective in the short term, compared with just 42 percent of Democrats.

A large majority of Trump voters - 85 percent - are confident in the plan in the short term.

But people across both parties tend to be less sure it is a durable strategy, slipping to 73 percent for Republicans and 34 percent for Democrats.

Fifteen percent of Trump voters also think it will be ineffective long-term.

DEMOCRATS DIVIDED

The poll shows Democrats are split over whether deploying the National Guard will curb illegal immigration.

Forty-eight percent see it as ineffective in the short term, while 42 percent see it as effective - a difference of just 6 percentage points.

Only 8 percent of Democrats say it will be “very effective,” but the same percentage think this for the long term as well.

The number of Republicans showing this strongest level of support in the long term drops slightly.

See graphic: tmsnrt.rs/2vAQ3lL

BORDER PATROL AGENTS

Trump has also called for more Border Patrol agents as part of his immigration crackdown.

Responding to a separate question in the poll, nearly 60 percent of Americans say they support the increase.

Democrats report similar views on the strategies: four in 10 support more Border Patrol agents and sending the National Guard as a short-term plan.

But more Republicans support upping border agents, at 83.5 percent, than deploying troops, at 77 percent.

This difference was narrower for respondents who voted for Trump in the 2016 election.

The Reuters/Ipsos poll of 1,516 U.S. adults on the National Guard border deployment was conducted April 15-19 and has a credibility interval of 3-6 percent.

For more Reuters/Ipsos polling, see: polling.reuters.com/