Here's some polling data

First, keep in mind that Biden dropped out late at night on the 21st. So any polling would need to be done since the 22nd to account for that. Some of the polls you see in the BG states were done with a hypothetical Trump/Harris matchup before Biden dropped out.

National Polls:

Ipsos poll for July 22-23 pulling from 1,018 registered voters:

Harris: 42%
Trump: 38%
Kennedy: 8%
MoE: 3%

Ipsos ran another poll with 1,241 adults (not necessarily registered voters):

Harris: 37%
Trump: 34%
Kennedy: 10%
MoE: 3%

And, finally, they ran a poll with 1,018 registered voters that did not include Kennedy:

Harris: 44%
Trump 42%
MoE: 3%

UPDATE:

Three more national polls dropped since I made my original post. All since Biden dropped out.

RMG Research did a national poll with 2,000 registered voters:

Trump: 48%
Harris: 46%
Kennedy: 2%
MoE: not listed

YouGov did a national poll with 1,435 registered voters:

Trump: 44%
Harris: 41%
Kennedy: 5%
Stein: 1%
West: 1%
Not sure: 5%
MoE: 3.1%

ActiVote did a poll of 1,000 likely voters putting Trump/Harris head-to-head with no independent candidates:

Trump: 50.5%
Harris: 49.5%
MoE: 3.1%


Now let's look at BG states:

Arizona:

July 19-20. Public Policy Polling asked 736 registered voters about a hypothetical Trump/Harris matchup with Kennedy and Stein included.

Trump: 46%
Harris: 40%
Kennedy: 7%
Stein: 1%
MoE: +/- 3.6%

Georgia:

Landmark ran a poll in Georgia with 400 likely voters. This was from July 22 and included several independent candidates:

Trump: 48%
Harris 47%
Kennedy: 4%
West: 1%
Oliver: 0%
Stein: 0%
MoE: +/- 5%

Michigan:

Public Policy ran a poll with 650 likely voters pitting Trump, Harris, Kennedy and Stein. This was taken on the 18th before Biden dropped out.

Trump: 46%
Harris: 41%
Kennedy: 6%
Stein: 2%
MoE: couldn't find it

Nevada:

Insider Advantage ran a poll with 800 likely voters. This poll is from the 16th before Biden dropped out.

Trump: 50%
Harris: 40%
MoE: +/- 3.52%

North Carolina:

Public Policy Polling ran a poll on July 19-20 with 573 registered voters:

Trump: 48
Harris: 44
MoE: +/- 3.6%

Pennsylvania

SoCal Research ran a poll on July 20th with 500 likely voters.

Trump: 50
Harris: 46
MoE: +/- 4.4%

Wisconsin:

Civiqs ran a poll on July 13-16 on 514 registered voters. This was before Biden dropped out.

Trump: 48%
Harris: 48%
Kennedy: 2%
Unsure: 3%
MoE: 4.8%

Conclusion:

Trump is losing nationally, but the numbers are within margin of error.

He is winning Arizona, Michigan, NC, and Nevada even after you factor in MoE.

Trump leads Georgia and PA but the numbers are within the MoE.

Trump/Harris are tied in Wisconsin.

Georgia is the only BG state that has had polling done since Biden dropped out.